Best Samsung Galaxy S III Trade-in Deals

Many are expecting that the new Samsung Galaxy S4 will be available as early as May, leaving users with a little more than a month to start saving for Samsung's new flagship phone. If your current phone is the Samsung Galaxy S III, however, you can help offset the cost of the upgrade by trading in your Android smartphone, putting some cash in your pocket that can go toward the cost of the new one.

Not unlike with an outdated iPhone, there are plenty of companies willing to give you cash or credit for an old Samsung Galaxy S III. But which companies are offering the best deals, which carrier models are valued the most and what's the catch? We checked out some of the most popular buy-back programs, including Gazelle, NextWorth, BuyBackWorld and BuyMyTronics, as well as trade-in programs through Amazon, Best Buy and RadioShack. Some trade-ins are are worth up to $306 for an unlocked version of the device, more than covering the likely $199 with new contract cost of the new phone.

All of the websites make the selling process easy, providing a printable shipping label that will deliver your smartphone directly to the buy-back company. Including transit time, most websites can take up to 10 business days to deliver the funds, although deposit times can be faster for services that offer electronic delivery of funds rather than a physical check. Amazon, Best Buy, Verizon Wireless and RadioShack only give gift cards to their respective stores, rather than cash that's offered by the competitors.

Each service offered a different amount depending on the associated carrier, with Sprint S III users getting the lowest trade-in value, users getting an average of $164 for a trade in versus the average of $184 across all cellular providers. BuyBackWorld offered the highest rate, $233 for a 16GB Galaxy S III in perfect condition, while NextWorth was the lowest, offering only $94 for the same phone.

T-Mobile users will get the most for their Samsung Galaxy S III, averaging $197 for the device, which is even higher than the average value of an unlocked S III, which was $193. The Galaxy S III for T-Mobile got the best value from Gazelle, offering $226, with RadioShack coming in a close second at $215. BuyMyTronics had the lowest buy-back amount for T-Mobile, giving users $154 for their phones.

Buy-back prices for AT&T and Verizon Wireless were very close, with AT&T pulling ahead slightly with an average value of $186 versus Verizon's $181. Gazelle valued the AT&T model the most, offering $226 for the Galaxy S III and just $200 for the same quality phone on Verizon. RadioShack was the opposite, giving $175 in store credit for a Verizon S III and just $168 for the AT&T model.

An unlocked Samsung Galaxy S III could fetch the highest trade-in value, even if it didn't have the highest average throughout all the buy-back companies. BuyBackWorld was offering $306 for an unlocked S III, with Gazelle in second place at $226. Amazon offered the worst value, only giving $84 in trade-in value for the same phone.

We tried to piece together some themes or patterns to the buy-back prices, but the numbers were mostly scattered somewhat randomly. BuyBackWorld offered the highest value on average, which was the case with the iPhone 4 and 4S as well. Gazelle was a strong contender, but NextWorth, which had decent prices for iPhone buy-backs, had some of the lower numbers with the Galaxy S III. RadioShack provided decent value as well, but might not be the best option unless you want store credit.